Abrasion testing machine



April 8, 1952 c. A. ROUNDS ETAL ABRASION TESTING MACHINE Filed Marh 10, 1948 Patented Apr. 8, 1952 ABRASION TESTING MACHINE Comer A. Rounds and Patrick A. Nestor, West Warwick, R.I., assignors to Chemo-Textiles, Inc., a corporation of Rhode Island Application March 10, 1948, Serial No. 13,978

This invention relates to new and useful improvements in abrasion testing machines. One object of the invention comprises, inter alia, a new and improved yarn abrasion testing machine.

This and further objects of the invention will be apparent from thefollowing description read in 4 conjunction with the drawings in which:

Fig. 1 represents a side view ofone construction in accordance with the invention;

Fig. 2 illustrates a perspective view of part of the construction shown in Fig. 1;

Fig. 3 shows an alternative embodiment of abrasion means, and I Fig. 4 illustrates a further alternative abrasion means. a

As illustrated in the drawings, I represents a base carrying an upright 2 and cross-piece 3. Freely rotatable roll 4 is mounted on cross-piece 3. At the other end of base I an upright 5 carries angle piece 6 pivotable at 1. Arm 8 of angle piece 6 carries, adjacent the end, weights 9 in stud I0. Any number of weights may be added or removed by inserting the stud through their central holes. The weights and stud rest loosely on arm 8, being supported thereon by way of a hole (not shown) through which stud I passes. The upper end of angle arm 6 carries freely rotatable roll II by Way of the angle piece I2 secured to upper arm 6 by the wing nut I3 and counter nut I4. An electric switch such as a micrcswitch I of the normally closed type carrying the spring leaf switch arm I6, is mounted on bracket II. In order to hold weighted arm 8 in position while inserting the material to be tested, a supporting wedge I8 is pivoted at I9 on Z piece 20. A motor 2| is mounted on base I and drives by way of gear box 22 stepped pulley 23, belt 24. and the stepped pulley 25. The latter is mounted by way of brackets 26 and 21 and bushing 28 onto upright 2, driving shaft 29 and thereto connected radial arm 30. A connecting rod 3I is adjustably secured to radial arm 30 by way of the-slot 32 and nut 33, being secured at its other end to excenter 34 by way of slot 35 and nut 36. Excenter 34 is excentrically secured to roll 38 for rotation on shaft 31. Roll 38 is rotatably mounted on shaft 39. A counting device 40 is positioned adjacent one end of the connecting arm 3I with its trigger arm 4| in registry with the radial arm 30. Counter 40 is of the conventional type having a slotted window opening in which the number of strokes imparted to the trigger M is registered for observance. Return screw 43 serves to return the counter to a predetermined value, such as zero,

"before the start of each operation. An electric main switch 44 controls the electrical circuit of motor 2I and microswitch I5 isin series in this circuit.

Inpractical operation the wedge piece I8 is brought into position to support arm 8, a testpiece 5 Cl aims. (01. 73-7) of yarn is brought onto roll 38 under guide roll 45, onto the freely rotatable rolls 4 and II, around the latter, back over the lower portion of roll 4, thence over guide roll 45a, and to the lower portion of roll 38. The test piece of yarn may be I looped to form an endless piece so as to be carried over most of the circumference of roll 38. It suffices, however, to secure the ends of the same to a post carried by the periphery of roll 38. A suitable rubbing surface is provided, as, for instance, by way of the rod 46 carrying a piece of abrasive crocus cloth 41. The shaft and the cloth on the shaft are so positioned that the upper portion of the yarn 48 is in rubbing contact therewith when the yarn is longitudinally moved. When using the particular kind of abrasive surface shown in Fig. 1, i. e., crocus cloth on a rod, it is of advantage to provide a bushing 49 having a cut-out window portion 50. The portion of the shaft beneath the window portion 50 is preferably graduated. In this way by moving the bushing 49 upror down in accordance with the graduations, the piece of crocus cloth is equally moved up or down, thus assuring that in any number of successive operations, the same surface is not used twice as this might interfere with the accuracy of the test and also to enable the operator to use a number of different surfaces on any single test specimen. a n

When the piece of testing yarn 48 is first secured, arm 6 and roll II will assume the position shown in solid outline in Fig. 1. In this position switch I5 is so arranged that the spring leaf I6 closes the motor circuit. When now turning the wedge I8 downward to assume the position as shown in dotted outline and turning on the main switch 44, the motor will drive by way ofgear box 22, pulley 23, belt 24, the pulley 25which in turn will rotate radial arm 30, moving connecting rod 3I at its one end around the shaft 29, resulting at its other end, by reason of the excenter 34, into an oscillating motion of the roll 38. As roll 38 oscillates back and forth, the piece of testing yarn 48,is rubbed back and forth over the abrasive surface of the crocus cloth 41. At the same time each forth, and back stroke triggers the counter, thus registering thereon. The piece of testing yarn is secured under tension by reason of the weights Qtending to pull roll II away from roll 4. After a certain number of the reciprocating movements, the piece of testing yarn will become abraded to a point where it snaps, thereby releasing roll II for self-movement down. This results in a downward motion of the arm 8 coming to rest on the stop 5 I (as shown in dotted outline) and thereby depressing the spring leaf I6 which in turn will break the electric circuit of the motor 2 I, thus stopping the motor and hence any further oscillating motion of the roll38. In this manner instantaneously upon the breaking of the yarn,

3 the mechanism is stopped and the counter will show the exact number of reciprocating strokes necessary to cause the breaking, by abrasion, of

the particular piece of test yarn.

In lieu of the abrasive surface of the crocus cloth shown in Fig. 1, a plain steel rod may be used. This is particularly to be recommended with thinner yarns where a lesser amount of abrasion may result in the parting of the yarn. Alternatively, the abrading surface within the scope of my invention may be provided by the yarn itself. In this case the yarn is threaded around rolls H and 4 in a multiple loop as, for instance, shown in Fig. 4. As there illustrated, roll H has been twisted to almost horizontal position,'-thereby twisting the yarn 48 so that upon a reciprocating motion of the yarn it will rub upon itself, the section 48a of the yarn furnishing' the abrading surface in that case. As illustrated, roll II is so mounted on the angle piece IZ that a loosening of the wing nut I3 will loosen theangle iron I! so that the same can be turned to any-desired position any number of desired times and be thereafter set in the desired position by the tightening of wing nut l3, thereby permitting the test piece to be abraded upon itself any desired number of times in the course of a single operation.

By way of still further alternative abrading surfaces multiple rods may be used. This is for in- -stancethe arrangement shown in Fig. 3 in which the test piece of yarn 48 is threaded in and out between rods 46a and 46b.

As will be seen from the foregoing, the invention thus essentially comprises an abrasion-testing machine having means for securing a testing piece under substantially longitudinal tension in rubbing contact with an abrasive surface, means operatively connected to said securing means for substantially longitudinally reciproeating such testing piece when so secured, means operatively connected to said reciprocating means for counting reciprocating strokes, and means operable by said securing means to stop said reciprocating means upon thebreaking of such testing piece.

More specifically and by way 'of preferred embodiment of and within the scope of the invention, the same preferably comprises at least one freelyrotatable-roll,aroll oscillating about its axis, reciprocating means for oscillatingsaid latter roll, said rolls being mounted for substantially longitudinally securing therebetween and along at least part of their circumferences, a test piece such as yarn, for rubbing contact with a surface, which may be part-of the testing .piece itself, said freely rotatable roll being mounted for substantially self-movement away from said oscillating roll upon the breaking of such testing piece, means operatively connected to at least one of said oscillating roll and said reciprocating means for counting reciprocating strokes and means preferably of the electrical switch kind, operable by said self-movement of said freely rotatable roll to stop said reciprocating means, such as by the breaking of a motor circuit upon the breaking of the test piece.

While we have described the machine of our invention in actual use in testing the resistance to abrasion of a yarn, it will of course be understood that its use is not limited to such a material and that it may, if desired, be used for testing any flexible longitudinally extending material such as wire, both plain and coated; cords, threads, tapes, belts, straps and ropes.

The foregoing description is for purposes of illustration and not of limitation, and it is, therefore, our intention that the invention be limited only by the appended claims or their equivalent wherein we have endeavored to claim broadly all inherent novelty.

We claim:

1. Abrasion-testing machine comprising at least one freely rotatable roll, a roll oscillating about its axis, reciprocating means for drivingly oscillating said latter roll, said rolls being mounted in alignment for securing a test piece therebetween and along at least part of their circumferences for rubbing contact with an abrasive surface, said freely rotatable roll being mounted for substantial self-movement away from said oscillating roll upon the breaking of such test piece, means operatively connected to at least one of said oscillating roll and said reciprocating means for counting reciprocating strokes, and means operable by self-movement of said freely rotatable roll to stop said reciprocating means upon the breaking of such test piece.

2. Abrasion-testing machine in accordance with claim 1 in which said means for drivingly oscillating said oscillating roll are electric means and in which said stop means is an electric switch in ciruit with said electric means, and operable by said self-movement of said freely rotatable roll to break said circuit upon the breaking of such test piece.

3. Abrasion-testing machine which comprises a first and second freely rotatable roll in substantially circumferential alignment, a roll oscillating about its axis, electric means for drivingly oscillating said last mentioned roll, said first, second and oscillating rolls being mounted in alignment for securing a test piece therebetween and along at least part of their circumferences for rubbing contact with an abrasive surface, pivotable arm means carrying said first roll, means operably connected to said arm, means for pivoting the same away from said second r011 upon the breaking of such test piece, a counter operatively connected to count strokes of said oscillating roll and an electric switch in circuit with said electric means and operable by said arm means upon the pivoting thereof away from said second roll, to thereby break said circuit upon the breaking of such test piece.

a. Abrasion-testing machine according to claim 3 in which there are interposed between said first and second rolls stationary abrading means positioned for rubbing contact with a test piece when secured on said rolls.

5. Abrasion-testing machine according to claim 4 in which said abrading means are secured to mounting means including means for variably positioning said abrading means and indicating means for showing registry position of different areas of said abrading means with the .path of travel defined by the reciprocating test piece.

COMER A, ROUNDS. PATRICK A. NESTER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,079,591 Bartell May 11, 1937 2,457,276 Ross Dec. 28, 1948 

